Radiation detection apparatus has many useful applications.
Ultraviolet radiation detectors are useful as fire detectors in various applications. In most applications, detectors capable of UV detection are directed towards the area of possible hazard and these detectors will respond to UV radiation transmitted over any unobstructed path from these areas. Obviously, it is necessary that these detectors be in condition to receive the UV in order to respond thereto and it is very important that the same be periodically tested to determine whether or not their radiation transmitting components are capable of transmitting radiation and whether or not the unit is capable of responding to the radiation that is transmitted from a fire.
This invention relates to an enclosure for a device which is best utilized for automatically determining whether or not the surfaces through which radiation must pass are free from radiation blocking or obstructing material.
The optical surfaces of a UV detection device include not only the surface of the UV detector through which radiation enters the sensing area but also include any components such as lenses, windows or the like which may be placed in front of the detector. Many installations require such additional components for various reasons and all optical surfaces must be considered for proper functioning of the detection device. Many different materials may accumulate on these optical surfaces and some of these materials could adversely affect the transmission of radiation from the hazardous area to the detector.
To overcome these problems, while providing a device that will not require a manual exposure of the detector to UV such as is often done by directing a source of UV at the detector from a point external to the detector, applicant has provided a device that will provide for monitoring of the otpical surfaces of the detector by the transmission of the UV radiation from a UV source to a reflective surface or surfaces that will direct UV back to the detector unit through the same optical surfaces that UV radiation from a fire must pass in order to allow the detector to respond to the fire.
It is therefore an object of applicant's invention to provide a device for the detection of radiation which will, in addition to detecting such radiation, monitor the optical surfaces through which the radiation must pass to insure the absence of radiation absorbing or blocking materials.
It is a further object of applicant's invention to provide a device for the detection of ultraviolet radiation from a fire which will also monitor the optical surfaces of the detector unit to insure the absence of ultraviolet absorbing or blocking materials.
It is a further object of applicant's invention to provide an enclosure for commonly housing a source of ultraviolet radiation and a detector of ultraviolet radiation while maintaining such source and detector in UV optically isolated relation to each other.
It is a further object of applicant's invention to provide an enclosure for a source of ultraviolet radiation and a detector for such radiation with means for directing radiation from such source outwardly from the enclosure and means for reflecting the outwardly directed radiation back to the detector through the same optical surfaces that the radiation from a monitored area would pass.
It is still a further object of applicant's invention to provide a detection unit for minitoring the optical surfaces through which ultraviolet radiation from a source such as a fire must be transmitted for the detection unit to respond.